fix application menu not being shown after KeePass is untrayed
add org.ayatana.bamf.matcher interface to listen for application events
add workaround for window not showing after minimize to tray
split into 2 plugins
* KeebuntuAppIndicatorExt.cs: Syncronize plugin initalization and
  make InvokeMainWindow async - it was locking up when exiting
  sometimes.

* KeebuntuAppMenuExt.cs: Syncronize plugin initalization
remove fixed references
add missing reference